In recent years, intra-body communication within human bodies using body channel communication has been developed for wearable and implantable biomedical devices and for data transfer through the human body. In general, body channel communication (BCC) is a form of wireless communication that uses the human body as the transmission medium. The signal is transmitted from a transmitter electrode through the human body to one or more receiver electrodes located on other parts of the body. BCC is attractive as signal attenuation through the human body is lower than signal attenuation through the air. In addition, the ability to support higher data rates and achieve lower power consumption gives BCC an edge over conventional wireless communication scheme such as Bluetooth for wireless body area network (WBAN) applications.
In most WBAN applications, the power consumption requirement for the transmitter is more stringent than that of the receiver, as typically the transmitter is either powered up wirelessly or operated with a smaller battery. BCC transceivers based on adaptive frequency hopping methods, dual band architectures, double frequency shift keying (FSK) modulation schemes, and direct digital architectures have been proposed. Among the proposed BCC transceivers, the direct digital architecture has the simplest and lowest power consumption transmitter design. Although, the direct digital architecture has the advantage of simple and low power transmitter architecture, it lacks the frequency selective ability to avoid strong interferences, and the data scalability necessary to meet high data rate requirements (>25 Mbps) for applications such as multi-channel neural recording.
One possibility to overcome the limitations of direct digital transceivers is to incorporate Walsh code into the baseband transceiver architecture. The frequency selective nature of the Walsh code provides the direct digital transceiver with interference avoidance capability, while the orthogonal characteristic of the Walsh spreading code allows for summation of codes to achieve higher data rate in band limited channel. Thus, integrating Walsh codes with baseband transceiver architectures allows for low power, bandwidth efficient, frequency selective and high data rate implementation of direct digital BCC transceivers. However, to utilize the entire usable body channel bandwidth of up to 80 MHz, the Walsh code baseband transceiver is required to operate at 160 MHz.
Thus, what is needed is a system and method for body channel communication baseband transceiver operation that supports both low power and high data rate modes while operating in the electric-field intra-body channel (40 MHz to 80 MHz). Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the disclosure.